Threading-die holder.



R. A. BOBHM.

THREADING DIE HOLDER.

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Patented Dec. 1, 191 1 niia I! I ve tor.

MMMM IN! mmms Print: no, I'HOYO urrm WAHINL ON n c UNITED sTA E s PATENT OFFICE.

RUDOLPH A. BOEHM, 0F ERIE, PENNSYLVANIA, ASSIGNOR OF ONE-THIRD TO FRED- ERICK W. WYATT AND ONE-THIRD TO GUSTAVE RAPP, BOTH OF ERIE, PENN- SYLVANIA.

THREADING-DIE HOLDER.

Specification of Letters Patent.

Patented Dec. 1, 1914.

To all whom it may concern:

Be it known that I, RUooLrrr A. Bomnr, a citizen of the United States, residing at Erie, in the county of Erie and State of Pennsylvania, have invented certain new and useful Improvements in 'lhreading- Die Holders; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will onable others skilled in the art to which it uppertains to make and use the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon, forming part of this specification.

My invention relates to threading die holders, and particularly to that type of said die holders which are adapted to automaticall open, after a desired number of threads have been cut.

The objects of my invention are to construct an automatically opening die holder with a tloatim shank, and with improved adjusting mechanism, so that various diameters of screws can be made by the same die. These and other features of my invention will a )pear hereafter in the specification and claims, and are illustrated in the accompanying drawings, in which Figure 1, is a plan view of the face of my die-holder, with a portion of the cam-ring broken'away. Fi 2, is a central section of the same, on the line m in Fi 1. Fig. 3, is a plan view of the same, wit 1 the cam-ring removed. Fi 4, is a'view partially in side elevation antI partially in central section, onthe line 1 -g in Fig. 3. Fig. 5, is a plan view of the same with the cam-ring, dies and adjusting ring removed. Fig. (l, is a side view of the same, showing an attachment for cutting threads on a. tapering screw. Fig. 7, is a section of the same on the line z-z, looking in the direction of the arrow in Fig. 4.

In these drawings, A, indicates the body of the die-holder, which is provided with a cylindrical chamber A, in the rear end thereof, and a central opening A, from the face thereof through into said chamber. The face thereof is provided with slots A, in which-are secured adjustable bearing plates (1, which are secured in adjusted position by means of screws (1. (see Fig. 3). The face end ofthe body A, is reduced in diameter so as to have a shoulder a, into which are cut grooves a, in which are placed springs a, as shown in Figs. 2 and 5. Upon the shoulder uf", I )lace a ring 13, which is provided with stu s 13', (shown in broken lines in Fig. 3, and in section in Fig. 5) projecting into the grooves a, and are engaged by the studs B on the ring B. The ring 13, 15 also provided with a slot 13, in which is placed a slidable block B, having atransverse slot 7), (see Fig. 8). I also provide adjusting screws B, by means of which the block 15, may be retained in adjusted position in the slot B", in the ring B.

Within the slots A, in the body A, I place thread cutting dies C, which are secured to chaser plates C, by means of screws 0; said chaser plates projecting under the adjustable face plates (1, in said slots A, so as to be retained in said slots by said face plates a. The outer ends of said chaser plates a, are provided with np-turned extensions G; I also provide springs C, (see Fi 3) which engage said extensions C and operate to assist in moving the dies 0, backward away from the work when desired.

Upon the rim B, I place a cam-ring D, which is provided with cam-surfaces D, which engage the outer ends of the dies C and operate to force them inwardly toward their work. The body A, within the camring D, is preferably of less diameter than the interior diameter of the cam-ring, so that the cam-ring D, will be in s )aced concentric relation to said body, so that should the work being threaded be sli htly off of center, the cam-ring D, and ies C, will center themselves upon it. The under face of the cam-ring D, is cut away sulliciently to receive the extensions C, on the extensions C, and is provided with cam-grooves D, which receive the up-turned projections C, on the die-chasers C, and operate in conjunction with the springs C, to force the dies (1, backward. The cam-ring D, is provided with a stud pin D". which projects into the slot 1), in adjustable block B, so that the cum-ring D, may be rotatively adjusted with relation to the ring B. The

ring D. is also provided on its under surface with a recess I3", (see Fig. 3) for the purpose hereinafter set forth.

Within the cylindrical chamber A, I place a floatin member E, having a central opening E, tlierethrough. In the central opening A, m the body A, I secure a sleeve E, which extendsinto the centralcpening E, in the floating member E The oating member E, is non-rotatably placed within the body A, by means of he -balls F, in grooves F, in the memberla, and F-in the body A. To retain the balls F, within the grooves F'-F, Ivv rovide keepers F, as shown in Figs. 2 an 7. In the floatin member E, I provide holes G G, in which place spring-pressed pins, G, which are maintained in contact with the body A, by means of springsg. I also provide recesses H H, partly in each 'of said members E, and the bed A, and I provide on the member E, smal lates e e? which extend into said recesses I H, and I secure on the rear end of the floating member E a hollow shank or stem J, by means ofwhichthe die holder may be supported in the machine tool in which it is desired to operate the die holder. In the recesses H H, I place s rin s h It. I then secure on the rear end 0 the ody 'A,'a collar or ring K, by means of small screws k, (see Fig. 2) which prevents the sprin s h and'h', from falling out ofthe recesses and-compresses said springs between'said ring K, and the plates 6 e, and thereby suspending the floatin member E, between the springs 9'0, and t e springs h It. The reeess'H, which receives the end of the plate a, 'is bored upward entirely throu h "the shoulder a, and in this recess a re L, is placed, which passes through the spring h and the late a, and terminates in a ead L, provided on its upper end with two bearing shoulders; 'the shoulder 'l,'be1n on the center 'of said shaft L, and the shoe der 1', being set away from the center of sa d shaft, so that the shoulder Z", does not allow thesprings a, to rotate the ring B, quiteso far 'as the shoulder Z, and cheer the other of said shoulders l and Z, can be used as desired by turning the lever L. This iswhat is known to the trade as a rough and finish attachment, where the lever L, and the shoulder Z, are in the position shown in the drawings, the dies are supposed to rou h-cut the threads, and when the lever L, is operated to 1present the shoulder Z, to act as a stop to tie ring B, theyvare su osed to finish-cut the threads. hen it s desired to cut a thread, the cam-ring D, is rotated backward a ainst the springs a-a, bv means of a hen e d, until the shoulders H, on the head of the spring pressed shaft L snaps into the recess 13, in the r ng 13, which forces the dies inward to then cutting position;'their cutting position relative to thediameter of the screw to be cut, being fixed by operating the ad usti ng screws B-B.. dies, a backward pull on the wor being threaded compresses the sprln s h and h,

and withdraws the shoulders Z out of-the recess 13, in the ring 'nyand emute 'th'e When it is desired to open the springs aa, to operate the two rings B and D, in the direction indicated by the arrows n, in Figs. 1, 3,4 and 6, which forces the dies backward from the work.

In -Fi 6, I show an attachment for cutting a tiread'on a tapered screw. On the camring heretofore described, I place a plate M, which by means of the bolt M, can

0 adjusted to give the edge of said plate any degree of inclination to the axis of the die-hol er described. Secured on the'body A, there is a guide N, in which there is secured a spring-pressed slide N, ada ted to be norma 1y maintained in an ex'ten ed position by '-'a spring N 0. in n, passing through 'a slot in said slide behind the springs, Upon this slide there is a hinged arm N, which is provided with a s ring to maintain it normally in contact with a stop shoulder n, on the slide N. The arm N, is provided with longitudinally adjustable mechanism N, by means of which the len th of said arm N may be varied, the said arm bein engaged by the inclined edge 'of the plate if, thereby limiting the rotation of the cam-rin D, by the springs a, as hereinbefore descri ed. n the operation of this taper'attachment the adjusting mechanism N, is operated to adjust the cam-ring D, to control the cutting dies in making a 'cut as desired, and when the dies start the thread on the work, the slide N, is engaged by the work holder or some part of the maciine tool-moving axially in unison with the work, '(not shown) and is thereby moved backward, thereby carrying the arm N, backward along the inclined edge -of the plate M, which permitsthe cam-ring D, to

e gradually rotated by the springs'a, in

the direction of the arrow n,thereby gradually opening the dies 0, during the cuttin of the threads, until the arm N, passes o of the-end =of-the plate M, and ermits the cam-ring D, to quickly open an withdraw the dies C, from their work. When the taper attachment is used, the shaft L, is removed-so'that'the plate M, and arm N, are the'stops which control the action of the springs a-'a.

Secured on the face of the body A, there is alate ring 0, which secures the camrin ,in' place on'the die-holder.

aving thus described my invention-so as to'ena'ble others to construct and operate the same, what I claim as new and desire to secure by Letters-Patent of the United States, is

'1. In a device-of the class described, a bodyhaving radial slots in -the face thereof and a cylindrical chamber in the opposite end, dies'in said radial slots, a cam-ring, cams thereon adapted to engage said dies and move them 'inwardiand outward, a shank in said cylinder chamber, a collar secured on the rearend of said body to retain said shank within: said; cylindrical chamber, spring mechanism adapted to maintain said shank in' spaced relation to the inner end of said cylindrical chamber, and spring mechanism adapted to normally maintain said'shank in spaced relation to said collar, and means to prevent said shank from rotatingwithin said chamber, substantially as set forth.

-2. In a device of the class described, a body having'a cylindrical chamber therein thread-cutting radial dies slidably mounte in the face thereof, a cam-ring mounted on said body, cams thereonadaptedto give inward and outward movement to said threading dies, spring mechanism ada ted to operate said rin to open said dies, ock mechanismvmounte in said body ada terl to controlsaid ring to maintain said ies in their innermost position, a shank, a head thereon slidably and non-rotatably mounted in the cylindrical chamber in said 'body,"a collar on said body adapted to retain said shank head within said chamber, spring-mechanism adapted to maintain said shank in spaced relation to the inner end of said cylindrical" chamber, and spring mechanism adapted to normally maintain said shank in spaced relation to said collar,'.and means on said head to engage said lock-mechanism and operate the same when 'saidyhead is moved toward said collar to releas'e-*said cam-ring and open said threading dies, substantially as set forth.

8. In a device of the class described, a bod havin a cylindrical chamber therein, radially sli able threading dies mounted in the face of said body, means to retain said dies therein, up-turned extensions on said dies, a cam-ring mounted on said body, cams thereon engaging said dies and extensions thereon for 1m arting radial movement thereto, spring mec ianism ada ted to operate said cam-ring to open said ies, a shank head slidable and non-rotatably mounted in said body, a collar secured on said body adapted to retain said head in said chamber, sprin mechanism adapted to maintain said shanc head in spaced relation to the inner end of said cylindrical chamber, and spring mechanism adapted to normally maintain said shank-head in s )aced relation to said collar, a spring-presse rotatable locking bolt slidabl mounted in said body and said collar a l urality of shoulders on the upper end 0 said bolt, adapted to stop the backward movement of said cam-ring at different points of rotation thereof, means to rotate said bolt means on said shank-headto operate said bolt to release said cam-ring and means to retain said cam-ring on said body, substantially as set forth.

4. In a device of the character described, a body member, a ringl having a recess in its under side, mounted tiereon, spring mechahaving a surface inclined to the axis body, a. bar slidably mounted on said body 130 nism to actuate said ring in one direction, a slotted slidable block mounted in the recess in said ring, screw mechanism to control said block, a spring-pressed slidable.lockbolt mounted in said body adapted to enter the recess in the under side of said ring when the same has. been operated in one direction, meansto release said bolt from engagement with said ring, radiall slidable thread-cutting dies secured in the face of said body member, spring mechanism engaging said dies and adapted-to move said-dies outwardly, a cam-ring rotatablymounted on said' body member, cams thereon adapted to give radial movement to said dies, astud on said cam-ring adapted to enter the slot in the slidable block in-spring actuated ring, and means to retain said cam-rin in place on said'body, substantiall as set forth.

5. In a device of the ciaracter described, a body member having a cylindrical chamber therein and a central openin therethrough, radially slidable threa -cutting dies mounted in the face thereof, a cam-ring mounted on said mcmber,-means to operate said ring, cams thereon adapted to give ra dial'movement to said dies, a sleeve secured in said central 0 ening and extendin into said cylindrical c iamber, a shank-hen slidably and non-rotatably mounted in said chamber having a central opening therethrough to receive said sleeve, a collar secured on said body adapted to retain said head within said chamber, spring mechanism adapted to suspend said head mid-way between the inner end of said chamber and said collar, a spring-pressed locking bolt slidably mounted in said body member adapted to engage and lock said cam-ring when said ring is o)erated in one direction, and means on sai shank-head to engage and operate said bolt to release said camring, substantially as set forth.

6. In a device of the class described, a body member, radially slidable thread-cutting dies secured in tie face thereof, a rotatable cam-rin mounted on said member, cams thereon a apted to give radial movement to said dies, spring mechanism adapted to rotate said IHlgdll one direction, an adjustable plate secured on said ring, a guide secured on said bodymember, a spring-pressed slide mounted in said guide, and means on said slide adapted to engage said adjustable plate to control the spring actuated rotation of said cam-ring, substantially as described.

7. The combination in a device of the class described, of a body member, radially movable threading dies secured in the face thereof, a cam-ring mounted on said body, cams thereon adapted to give radial movement to said dies, a plate secured on said cam-rin of sai Earallel to -the'axis'of said body ada ted to e engaged bysome moving part of-t 1e machine, upon which the device is used, a spring to operate said bar in one direction, and adjustable mechanism carried by said bar adapted to engage the inclined surface on said plate to control the rotation of said cam-ring in one direction, substantially as set forth.

8. In a device of the class described, a body member having radial slots in the face thereof, bearing-plates removably secured in said slots, die-,platcs-in said slots extending under said 1 lates, upturned extensions on said plates, t iread-cuttin dies between said bearing-plates and secure to-said die-plates, a cam-ring mounted on said body, cams thereon adapted to engage said dies and said upturned extensions, and means to o erate said cam-ring, substantially as set fortii.

9. 'In a device of the class described, a body member-having a cylindrical chamber theiein, radially movable thread cutting dies mounted in the face thereof, means to op- 4 erate said dies, a-shankhead slidabl mounted in said member, a collar on sai body to retain said head in said chamber, co-incident longitudinal grooves in the wall of said body member and periphery of said shank head, balls in said grooves,and spring mechanism adapted to suspend said -head midwa between the inner end of said-chamber an' saidcollar, substantially as set forth.

10. In adev-ice of the character described, a body member having a c lindrical chamber therein, \radiall movab e threading dies in the face thereo means to o erate said dies, a. shank head in said cham er, spring pressed ins in said shank head adapted to engage e inner end of:said chamber, ball race-ways bet-ween the wall of said chamber and said-head, balls in said race-wa s, and springs between said head and -s ai collar operating in opposition to 881d spring pressed pins substantiallyas set forth.

11. In a evice of the class described, a body member, radially :movable threading dies secured in the face thereof, -a cam-ring secured thereon in spaced concentric relation thereto adapted to move said dies radially, and means to rotate saidcam-ring, substantially as set iorth.

In =testimoni whereof I afiix my signature, in presence 0 two witnesses.-

RUDOLPH A. BOEHM.

Witnesses:

H. M. S'runesos, Mormon Ecnons.

Copies of this potent may be obtained or five cents each, braddreulag-tho Commissioner of Patents, wuhlngtoynac." 

